Perennial crops topic of Granada field day
By Janet Kubat Willette
Date Modified: 08/17/2011 3:40 PM
GRANADA, Minn. — A monarch butterfly fluttered in the prairie cone flowers and wild bergamot as about 30 people walked past on their way to learn more about the research project that brought the native plants to farmland along Elm Creek in Martin County.
The native plants, along with hybrid willow and hybrid popular trees, are planted on 5.3 acres leased from Darwin and Sandy Roberts. The land north of Granada is prone to flooding, with all or part of the plot underwater four or five times since it was planted in May 2010, Darwin Roberts said.
"It's a wonderful, rich, fertile soil," he said, which is confirmed by the soil test he does every other year. It's also a deep silt soil. Last year, beans planted in the field yielded 63.5 bushels to the acre, but he couldn't harvest them because they were flooded after the September flood. Water covered the entire 30-plus acres. The field is surrounded by Elm Creek on three sides.
The land has been in Roberts' family for nearly a 100 years and he remembers when a good portion was in pasture. Now, he raises corn and soybeans, but has applied through the Natural Resources Conservation Service to enroll 22 acres in a Reinvest in Minnesota Wetland Restoration Program easement. If accepted, it's unknown if U of M research will be allowed to continue.
A Martin County Soil and Water Conservation District supervisor, Roberts hopes to see if the perennial crops planted in his field can make a difference for water quality, water quantity and if they provide other ecological and environmental benefits.
"I guess I love research," he said.
Everything doesn't have to be corn and soybeans. Alternative crops also have a place on the landscape, he said.
They aren't doing this type of perennial crop research because they are tired of looking at corn and soybeans, said Gregg Johnson, University of Minnesota associate professor of agronomy and plant genetics based at the Southern Research and Outreach Center in Waseca. Rather, it's about designing a cropping system to have multiple values and multiple benefits. It's about about designing an alternative crop system that is sensible and realistic and looks ahead to the bioenergy markets that may emerge down the road.
The crops have different harvest intervals. The willow, for example, can be harvested once every three years for about seven times, Johnson said. Poplars are harvested at four or five years and their regrowth isn't as substantial as willows.
The research taking place on the Roberts' land will help researchers determine what pairings work best together, said Josh Gamble, a master's student at the University of Minnesota. The research projects under way include: Alley cropping with hybrid willow and hybrid poplar rows separated by herbaceous plants, and cover crops in hybrid willow and hybrid poplar rows.
It's a mixed buffer system to reduce the overland flow of runoff, Gamble said.
The overland flow of water carries with it sediment, organic matter and nutrients, said Doug Miller, area soil scientist for the Natural Resources Conservation Service in St. Peter.
All soil has a purpose and use, it just needs to be managed properly, Miller said. The trick is to think in terms of multiple benefits and to manage the land that way.
Roberts has noticed that the young perennials already trap silt, rather than letting it slip away into the creek as it recedes back into its banks after a flood event.
"This is a good buffer," he said.
The University of Minnesota is leasing the land for four years with an option for a fifth year.
The July 21 field day was hosted by several partners, including Rural Advantage, the Natural Resources Conservation Service and University of Minnesota Extension.